This disclosure relates to gas turbine engines, and more particularly to stator vane arrangements for gas turbine engines.
A gas turbine engine typically includes a rotor assembly which extends axially through the engine. A stator assembly is radially spaced from the rotor assembly and includes an engine case which circumscribes the rotor assembly. A flow path for working medium gasses is defined within the case and extends generally axially between the stator assembly and the rotor assembly.
The rotor assembly includes an array of rotor blades extending radially outwardly across the working medium flowpath into proximity with the case. Arrays of stator vane assemblies are alternatingly arranged between rows of rotor blades and extend inwardly from the case across the working medium flowpath into proximity with the rotor assembly to guide the working medium gases when discharged from the rotor blades. Some stator vane assemblies, such as those at an entrance and or an exit of a fan or low pressure compressor portion of the gas turbine engine, are formed as contiguous rings with an annular outer shroud and an annular inner shroud and stator vanes rigidly fixed to and extending between the inner shroud and the outer shroud. The inner shroud and the outer shroud may both be fixed to stationary structure of the gas turbine engine.
Since the stator vanes are rigidly fixed to the inner shroud and outer shroud, the stator vanes are configured with aeromechanical tuning of vibratory modes, which often results in the vane deviating from an optimal aerodynamic shape.